Apparatus for and process of pulping wood



(No Model.)

' H. A. PRAMBACH.

APPARATUS POR AND PROCESS OP PULPING W'OD.

No. 258,400. l Patented Mey 23, 1882.

N, Pneus. Phmmmnngmpner, wwngwn. n. c.

f UNITE@ STaTns .PATENT Ormes.

HENRY A. FRAMBACH, OF KAUKAUNA, WISCONSIN.

APPARATUS FOR AND PROCESS OF PULPING WOOD.

SPECIFICATION forming part of Letters Patent No. 258,400, dated May 23, 1832.

Application tiled May 17, 1881. (No model.)

To all whom it may concern Be it known that I, HENRY A. FRAMBAoi-r, of Kaukauna, in the county of Outagamie and State of Wisconsin, have invented certain new and useful Improvemeu ts in Apparatus for and Process of Pulping Wood; and I do hereby declare that the following is a full, clear, and' exact description of the invention, which will enable others skilled in the art to which it appertains to make and use the same, reference being had to the accompanying drawing, and to letters of reference marked thereon, which form a part of this specification.

My invention relates to improved process of and apparatus for the treatment ot' wood preparatory to its reduction to paper-pulp, and will be fully set forth hereinafter. y

The drawing is a vertical central section. of the apparatus by which I carryout my invention.

A is a tub or vat, preferably made of wood, and usually about ten feet in diameter and eleven feet deep, provided with a perforated false bottom, E, placed about fteen inches above the bottom of the tub, and thus forming a water-chamber, B, below the false bottom. The top of the tub is tightly covered and provided with a man-hole, covered by a hinged lid, o, adapted to be bolted securelydown when the tub is closed for work. Just below the cover of the tub I secure the deliector D, consisting of a large circular metallic plate. Through the center of the tub or vat I extend a vertical pipe or tube, C, about two inches in diameter, whose upper end opens near the top of the tub, a few inches below the deliector, and whose lower end extends below the false bottom and opens near the true bottom ofthe tub, being surrounded by an annular guard or basin, b, which is tightly secured to the bottom ofthe tub and extends upward to aboutonehalf the height of the water-chamber B, so that all fluid which enters the tube (l must pass over the upper edge of the annular guard, thus effectually preventing any precipitated matter from entering` the said tube. A small steam-pipe, a, about three-fourths of an inch in diameter, is led from a steam-boiler (not shown) down the inner side of the tub, and along the true bottom through the annular guard, and its lower end is thence projected up into the lower end of the tube C, above the level of the water-chamber B, to serve as an injector, as hereinafter explained.

The object of my invention is to cook the gummy or resinous matter out of the wood, so as to leave only that part ofit from which the paper is made, and the operation is as follows: Taking the wood in its natural state, with the bark on, it is reduced to pieces of a suitable size and introduced into the tub through the man-hole in the usual way, and water is then introduced, which runs down until it has nearly or quite filled the chamber B. The lid c is then bolted down, making the cover perfectly tight. Steam is then turned on through the pipe a, which, as it rushes up pipe (l, creates a vacuum therein, into which water from the chamber B rises, covering the steariioritioe, at which point it is momentarily arrested and partially converted into steam, and is then, by expansion, thrown up against the detlector and over upon the material being treated in intermittentjets of intermingled spray and steam at a very high temperature, thence permeating the material in the tub, the steam melting out the resinous matter and the condensed spray trickling down to the chamber B, carrying with it the resinous substances cooked ont ot' the wood by the steam and preventing any deadening of the fibers of the wood without destroying the tenacity thereof, and thus I subject the wood to the combined and simultaneous action of both steam and watersteam to do the cooking and water to prevent deadening and to carry off the impurities. The water bearing the impurities, which enters the chamber B through the pertbrationsin the false bottom E, is prevented from again entering pipe C by the annular guard or flange b, already described, until after the said impurities have had time to settle by gravity to the bottom of the tub, when the water, freed of resinous matter, may llow over the guard and be again drawn up tube C by the steam-jet.

The impurities can be removed as often as may be necessary through any suitable outlet in the lower part of the tub.

By the intermittent action of my'device (there being a momentary stoppage of water at the mouth of the steam-pipe before each partial vaporization and ejection) only sufficient rco water is thrown upon the wood to preserve the tenacity of' the fibers and to carry olf the impurities without lowering the temperature of the steam, as would occur if the steam were iiitroduced from below and tliewater from above, or if the steam and water were alternately admitted to the tub; and I am thus enabled to thoroughly purify the wood in a few hours, iustead of four or tive times as long, as would be necessary by the other processes or with a lowered temperature, and the wood is subjected to a cooking and washingaction, whereby it becomes thoroughly freed from itsimpuritics and in suitable condition for the subsequent operations ot' grinding and pulping, the entire operation requiring only three or four hours.

In treating some woods I prefer to use alkaline water or other solvents of gum or resin; and I have found by experiment that the addition ot' potatoes to the water has the best et'- fect in dissolving` the gums and imparts a very light color to the finished pulp.

A great advantage of my process over those formerly in use consists in my ability to einploy the wood in its natural state, with the bark on, instead of first stripping off the bark, asformerly. upon the adhesiveinatter that unites the bark and inner wood together is such that this guiniiiy matter is dissolvedout, and l thus save about fifteen per cent. in labor formerly expended in first stripping the baik, which in my process becomes loosened and readily separable when the wood is in condition for trans fer to the grinding apparatus.

.I am aware that heretofore wood has been prepared for pulping by having hotI water passed continuously through the wood body in a closed tank, the water being introduced through a sprinkler at the top, and thus melting out the resinous matter; and I am also aware that water has been introduced from above, while steam has been admitted from below, to cleanse wood contained in a closed tank; but I have already pointed out the disadvantages of these processes, the water, when used alone, requiring along time to thoroughly cleanse the wood, and tending, when steam is admitted from below, to lower the temperature ofthe steam, which likewise greatly increases the time required for the proper preparation or purification of' the wood. I have also referred to the alternate action ot' steam and water, which has the saine e'ect-namely, lower- The action of' the steam and spray i ing the temperature of the steam, and thereby delaying the cleansing process. So far as I am aware I ain the first to admit the steam and water simultaneously in intermittent mingled jets, as well as the first to admit the steam from above, with only sufficient water to prevent the deadening of the fibers of' the wood; and I also believe I am the tirst to subject the wood to the described cleansing action without first stripping off' the bark, all of which features result in a very considerable saving ot' time and expense, and hence are ofthe greatestimportanee in the art.

Having thus described my invention, what I cla-im as new, and desire to secure by Letters Patent, is-

l. The process of preparing wood for pulping, consisting in subjecting it to the simultaneous action ot' intermittent jets of mingled spray and steam, as set forth.

2. rllie process ot' preparing wood for pulping, consisting in subjecting it, in a closed vessel, to the combined and simultaneous action of steam and spray introduced within the vessel from above the wood, as set forth.

3. In the preparation of' wood pulp, the process of purifying the wood, consisting in cooking out the resinous matters wholly by steam, combined with only sufficient water' to carry ott' the impurities and preserve the tenacity ot' the tibers of the wood without deadening them and without lowering the temperature ot' the steam.

et. Ina wood-piilpiiig apparatus, the combiiiatiou ofthe closed vessel A, perforated false bottom E, steam-injecting pipe a, open tube C, dellector D, and annular flange b, substantially as shown and described.

5. In the preparation ot' wood pulp, the process of subdividing the wood while in a nat` ural condition, with the bark on, and subjecting it to the described combined and siiiiultaueous action of'steam and spray, whereby the natural gum uniting the bark and wood is dissolved out, enabling their subsequent easy separation and avoiding any preliminary stripping otf' of bark, as set forth.

In testimony that I claim the foregoing as my own invention I affix my signature in presence of two witnesses.

HENRY A. 'FRAMBAGI'L \Vitnesses:

Guo. F. GRAHAM, Giras. F. S'rANsBURY.

IOO 

